Genetic structure of a nematode parasite (Trichuris muris) across the European house mouse hybrid zone

0425721 - ÚBO 2014 CZ eng A - Abstract
Wasimuddin, Wasimuddin - Bryja, Josef - Piálek, Jaroslav - Baird, Stuart J. E. - Ribas, Alexis - Goüy de Bellocq, Joëlle
Genetic structure of a nematode parasite (Trichuris muris) across the European house mouse hybrid zone.
Zoologické dny Ostrava 2014: sborník abstraktů z konference 6.-7. února 2014. Brno: Ústav biologie obratlovců AV ČR, 2014 - (Bryja, J.; Drozd, P.). s. 219-220. ISBN 978-80-87189-16-0.
[Zoologické dny. 06.02.2014-07.02.2014, Ostrava]
R&D Projects: GA MŠMT EE2.3.35.0026
Institutional support: RVO:68081766
Keywords : parasites * house mice
Subject RIV: EG - Zoology

A continuous arms race between hosts and parasites may lead to co-adaptations varying both spatially and temporally. In secondary contact hybrid zones between divergent host taxa, these co-adaptations may break down, leading to a higher/lower prevalence of parasites in hybrids and a barrier to parasite gene flow at the centre of host contact. Here we aimed to study the genetic structure of a common gastrointestinal nematode parasite, Trichuris muris (Trichuridae) of the house mouse (Mus musculus) in the European house mouse hybrid zone (HMHZ). Specifically, we asked i) Are parasites genetically structured according to the host hybrid zone? ii) Could there also be a hybrid zone between the parasites? We analyzed 195 worms from 60 localities (one nematode per wild caught house mouse) covering an area of 6,500 km2 in Central Europe (Czech Republic and Germany). We sequenced the mitochondrial cytochrome oxidase-I (COXI) gene and genotyped three microsatellite markers from these parasites. We found 26 haplotypes in COX-I sequences which, by performing haplotype network analysis grouped into two large and two small clades. However, the geographic pattern of these parasite mt clades did not correlate with host genotype across HMHZ. Hierarchically clustering (Structure, k=2 to k=10) the parasite microsatellite data suggests distinct clusters, but again with no correlation to the east-west host contact. Our results strongly contrast with the genetic structure of another nematode, Syphacia obvelata which mirrors the host HZ geography. We suggest this contrast is due to the lesser host specificity of T. muris compared to S. obvelata. In the sampled field area, the house mouse is sympatric with woodmice (genus Apodemus) or rats (Rattus norvegicus), both being common hosts of T. muris. Such alternative hosts provide a way round any transmission barrier. Furthermore, presence of similar mt haplotypes and microsatellites alleles in worms from woodmice supported this assumption. In conclusion, T. muris is not genetically structured according to its host in the HMHZ and there is no evidence of hybrid individuals.
Permanent Link: http://hdl.handle.net/11104/0231598